Recessed luminaires are widely used in new-construction applications and/or remodel applications because they provide for a wide variety of illumination patterns for various uses while the fixture structure is itself hidden from plain view within a plenum space between a lower finished surface ceiling (herein ‘lower ceiling’, also interchangeably referred to as ‘ceiling’) and an upper structural ceiling (herein ‘upper ceiling’). In remodel applications where a lower ceiling (e.g., ceiling drywall) is already in place and there is little or no access to support structures (e.g., joists) in the space above the lower ceiling, the recessed luminaires are installed through either pre-existing apertures or newly created apertures in the lower ceiling. Often, the pre-existing apertures may be small (in diameter) or the lower ceiling having the pre-existing or newly formed apertures may be thick (e.g., 1 inch to 2 inches).
Conventional recessed luminaires are not configured for easy installation through such small apertures in the ceiling or through apertures that are formed in a thick ceiling, especially when the plenum space above the ceiling is shallow. Further, recessed luminaires may commonly encounter the problem of excessive heat buildup which can affect the electrical wiring cables or ducts in the plenum space. As a solution, recessed luminaires are provided with thermal protectors or thermoprotector means (herein ‘thermoprotectors’) that are configured to interrupt an electrical power to a light circuit of the recessed luminaires if the temperature associated with the recessed luminaires exceeds a certain preset value.
In conventional recessed luminaires, said thermoprotectors may be disposed inside or outside the recessed housing can of the recessed luminaire using a thermoprotector casing. The thermoprotector casing may result in additional end user cost. Further, the thermoprotector requires additional wiring to be routed through or disposed in the interior of the recessed housing can which may be undesirable, especially in smaller recessed housing cans designed for installation in tight spaces (e.g., shallow plenum space).
Furthermore, junction boxes of conventional recessed luminaires increase the footprint of the recessed luminaires because the junction boxes are designed to support transformers on an outer surface of the junction boxes in separate transformer enclosures away from the electrical wiring in the junction boxes. This in turn increases the footprint of the conventional recessed luminaires. The larger footprint of the conventional recessed luminaires may be undesirable, especially for installation in tight spaces or applications where access to the plenum space above the ceiling may be limited, e.g., remodel applications.